(1) Field of the Invention
The present invention relates to a holographic optical pickup device, an optical information recording and reproducing apparatus, and a method of recording and reproducing optical information for recording or reproducing information on an optical information recording medium using holography.
(2) Description of the Related Art
Recently, a double luminous flux angular multiplexing method has been proposed as the holography that allows high-speed recording/reproduction of large capacity of data. This approach requires control of the relative angle between the signal beam and the reference beam with high accuracy. Aiming at satisfying the requirement, the technique as disclosed in US 2009/0207710 detects the signal beam using the image sensor for searching the relative angle between the signal beam and the reference beam, calculates the SNR for each recorded angle, and predicts the subsequent relative angle based on the calculated value so as to control the relative angle of the reference beam with respect to the signal beam.